PERPETUAL MOTION 67 



effected in the cost of running an engine. At that time 

 gasolene and benzine were unknown in commerce, and the 

 same was true in regard to bisulphide of carbon, but as 

 the process of manufacturing the latter was simple and the 

 sources of supply were cheap and apparently unlimited, they 

 adopted that liquid. The name of one of these inventors 

 was Hughes and that of the other was Hill, and it would 

 seem that each had made the invention independently of 

 the other. They had a fierce conflict over the patent, but 

 this does not concern us except to this extent, that the 

 records of the case may therefore be found in the archives 

 of the Patent Office at Washington, D.C. Hughes was 

 backed by the wealth of a well-known lawyer of Rochester, 

 whose son subsequently occupied a high office in the state 

 of New York, and he constructed a beautiful little steam- 

 engine and boiler, made of the very finest materials and 

 with such skill and accuracy that it gave out a very consid- 

 erable amount of power in proportion to its size. The 

 source of heat was a series of lamps, fed, I think, with 

 lard oil (this was before the days of kerosene), and the ex- 

 hibition test consisted in first filling the boiler with water, 

 and noting the time that it took to get up a certain steam 

 pressure as shown by the gage. After this test, bisulphide 

 of carbon was added to the water, and the time and pres- 

 sure were noted. The difference was of course remark- 

 able, and altogether in favor of the new liquid. The 

 exhaust was carried into a vessel of cold water and as bi- 

 sulphide of carbon is very easily condensed and very heavy, 

 almost the entire quantity used was recovered and used 

 over and over again. 



But to the uninstructed onlooker, the most remarkable 

 part of the exhibition was when the steam pressure was so 



